I should have said, the only credible source I've come across in 15 years of intensive work with inkjet materials. I'll ask, who else is there? Point me to them and I'll check them out. Aardenburg is unbeholden to any manufacturer, has tested ink and substrate materials relevant to real artists and printers rather than simple OEM combo offerings, including many of interest to advanced niche workers.
More importantly I've never seen them state an ink, paper, or combo as "archival", now a meaningless marketing term. or even say a given setup will last "x" number of years, another dead give-away of questionable intent.
It seems after all the smoke has cleared, if we accept that accelerated fade testing is useful (what else can we do?) then the only credible conclusions are that a given combination of materials, in a given environment, will change in "this" fashion in "this" amount of time. And that info is helpful in countless ways, not only in how we choose materials, but how we care for the art once made.
Perhaps my statement was a bit overly adamant, but I think Mark speaks for his work on a regular basis far better than I can, and has conducted his work impressively, and the results have been enormously valuable to myself and many others. I can recall no challenge of merit to his approach or results. If you can point me to more sources of relevant similar work, I'll definitely make use of it.
quick edit- I didn't mean to hijack the thread. AIS inks may have excellent longevity but I wish they were in for testing. Also, longevity is not always all users' priority, including my own under certain circumstances. I do hope we hear more about these inks